325_driver 422 Report post Posted July 20, 2007 Hey guys ok so my car starts fine, accellerate fine, but after 15 minutes of so of driving i would encounter this . . .. : (i will try and explain) The car will have trouble accelerating past 5000 rpm with out severe juddering or the engine dying If i keep running it the problem will get worse and eventually not start at all. I replaced the external fuel pump, and the problem was not so bad, but still died round 5000 rpm etc Could the fuel filter be seriously blocked ?? Can that actually cause the car to die completely as i just thought it slowed it down. and 2ndly, i was reading up on a previous post a while ago about older models have a internal pump also, to keep the external pump primed (sometimes a great whining noise will come from the back seat i think it might be the pump). (i have a 1986 325i prefacelift) Can some one try and diagnose this problem, i am just hoping it is some thing as stupid as my fuel filter. Cheers guys Quote Share this post Link to post Share on other sites
jochen 4 Report post Posted July 21, 2007 Hey guys ok so my car starts fine, accellerate fine, but after 15 minutes of so of driving i would encounter this . . .. : (i will try and explain) The car will have trouble accelerating past 5000 rpm with out severe juddering or the engine dying If i keep running it the problem will get worse and eventually not start at all. I replaced the external fuel pump, and the problem was not so bad, but still died round 5000 rpm etc Could the fuel filter be seriously blocked ?? Can that actually cause the car to die completely as i just thought it slowed it down. and 2ndly, i was reading up on a previous post a while ago about older models have a internal pump also, to keep the external pump primed (sometimes a great whining noise will come from the back seat i think it might be the pump). (i have a 1986 325i prefacelift) Can some one try and diagnose this problem, i am just hoping it is some thing as stupid as my fuel filter. Cheers guys Sounds like it could be low fuel pressure. I had a Fiat Tipo once with a fuel pump so clogged that it couldn't deliver sufficient fuel pressure to feed the engine under load. I used to get to 90kmph OK on the motorway and then struggle to go any faster because It couldn't feed the engine fast enough. Doing a pressure check with a pressure gauge told me immediately what the problem was - way too low fuel pressure. so get your fuel pressure checked. Quote Share this post Link to post Share on other sites
hotwire 352 Report post Posted July 21, 2007 Sounds like it could be low fuel pressure. I had a Fiat Tipo once with a fuel pump so clogged that it couldn't deliver sufficient fuel pressure to feed the engine under load. I used to get to 90kmph OK on the motorway and then struggle to go any faster because It couldn't feed the engine fast enough. Doing a pressure check with a pressure gauge told me immediately what the problem was - way too low fuel pressure. so get your fuel pressure checked. Jochen, What on earth did you want to own a Fiat Tipo for?? That leading to an E39 540i - hardly a comparison. Agreed though, get your fuel pressure/flow checked. Be aware that sometimes there can be good pressure but with poor flow rate (filter or pump/s) I have had both these senarios causing low flow & the problem discribed in the thread Quote Share this post Link to post Share on other sites
jochen 4 Report post Posted July 21, 2007 Jochen, What on earth did you want to own a Fiat Tipo for?? That leading to an E39 540i - hardly a comparison. Yeah but I remember hooning up the Austrian Alps in the snow in my front-wheel drive light-weight Fiat Tipo passing all the BMWs and Mercedes who had to stop to fit chains :-) It was a fun little car, but you could never pull it apart and put it together again without breaking something.... Quote Share this post Link to post Share on other sites
hotwire 352 Report post Posted July 21, 2007 Yeah but I remember hooning up the Austrian Alps in the snow in my front-wheel drive light-weight Fiat Tipo passing all the BMWs and Mercedes who had to stop to fit chains :-) It was a fun little car, but you could never pull it apart and put it together again without breaking something.... Agreed on both counts - they are pricks to work on, the French stuff a close second I reacon Quote Share this post Link to post Share on other sites